In a high-voltage propelled vehicle (HVPV), such as a hybrid-electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), a fuel cell electric vehicle (FCEV), or an electric vehicle (EV), a high-voltage (HV) power supply or energy storage system (ESS), for example a rechargeable battery pack or other HV electrochemical energy storage device, provides a source or supply of at least a portion of the HV electrical power required for propelling the vehicle. In some configurations an internal combustion engine can shut off or selectively power down whenever the vehicle is idling or at a standstill in order to conserve fuel, and/or the vehicle can run entirely on HV electrical power provided by the ESS, depending on the particular design of the vehicle.
To provide sufficient HV electrical power for partially or fully propelling the vehicle, as well as to energize various HV components onboard the vehicle, the ESS contains or stores a relatively high potential energy or voltage, typically on the order of approximately 60 to 300 volts or more. Common HV components used onboard a typical HVPV can include, for example, one or more electric motor/generators, an air conditioning control module (ACCM), a power steering controller, a power inverter module (PIM), an auxiliary power unit or module (APM), and/or other HV devices.
Within a given HV vehicle component, the HV electrical connection is ordinarily made by bolting or fastening a standard 2-phase or 3-phase HV electrical cable to an HV receptacle and/or a bus bar. To protect against unintended access to the HV circuit onboard the vehicle, many manufacturers utilize what is known as a high-voltage interlock loop or HVIL circuit. An HVIL circuit is a specially adapted low-voltage circuit usually energized by a 12-volt auxiliary battery, and adapted for disconnecting an HV power supply while safely discharging any localized electrical energy charge. The HVIL circuit is commonly routed to a potential HV access point, such as a connection box or splicing junction into an HV device. The HVIL circuit senses any potential access to the HV access point by detecting a change in certain electrical characteristics of the low-voltage wires or lines forming the HVIL circuit.
Typically, the HVIL lines are routed to the same locations or access points in the vehicle as are the HV cables. Conventionally, therefore, low-voltage HVIL lines are co-bundled with the HV cables and routed in tandem to the various HV access points. However, bundling in this manner can be less than optimal due largely to the widely disparate gages of the respective sets of lines or cables. Any vibration, motion, or bending of the relatively large gage HV cables can potentially affect the durability of any co-bundled smaller gage HVIL lines over time. Moreover, regardless of the durability concerns raised by bundling disparate gage wires or cables in a dynamic system such as an automotive vehicle, conventional HV connection methods also do not optimally determine whether an HV connector is properly in position or is properly installed before an HVIL circuit is closed.